A lightbox not of images but of embedded code?

Hello
My problem is on several levels:

I need to create a huge collection of images (probably 5000)
I connected cloudinary to a webflow CMS via zapier… and it works (so far)…
But I end up with embedded codes to display the images… I don’t know how to handle such a large image compilation with embed codes instead of images…
I tried to cobble together a design to display large images (like a lightbox) but each click opens a new page, since it’s a new item in the CMS collection… which makes it very heavy if you want to view quickly…

I’m bugging… how to create a lightbox based not on webflow images but on hosted URLs (embedded code)? While keeping a smooth user experience…
Is it wise to use a lightbox system with so many images?